Since there were some mentions both ways about Lelouch being alive or dead at the end of the second season I will put in my two cents plus my reasoning. Before I start, there is no proof either way, they left it as an open ending on purpose to make you think about it, this also means that they can come up with their own answer at a later time if they so wish. Personally I believe that Lelouch is alive: 1. Back in C2's world when Lelouch met his father and realized that he was now an immortal from having taken V2's code V2 was still alive in the real world. He may have been in pain and dying of his wounds but alive none the less. This means that the transfer of the code to a recipient of geass makes the former owner of the code mortal but doesn't cause instant death. 2. C2 wanted for her "contract" to be completed but although it was never put into words it was blatantly obvious that she wanted someone to truly love her, this person was Lelouch and he realized it and stopped his father from taking her code, so he intended to go through with completing her contract at some point. 3. Lelouch was brilliant. Maybe egotistical at times in the series and a bit odd, but definitely not an idiot. He knew my former two points before he came up with his "Zero Requiem" much less before he went through with it. Why would he have not thought about taking over C2's code before that parade and then letting himself be "killed" so that peace could reign, and then go live out the quiet life. 4. Now the two ways that they hinted at the fact that he could be alive without making it proven so that way they could mess with us a little. When he was just stabbed and he is talking with Suzaku he says a few lines and then Suzaku replies, "this geass I do accept" or something like that. Only someone with a code not someone with geass can give others the power of geass. It can be seen as a hint that Lelouch has a code now. 5. The other one is as often mentioned when C2 is in the back of the wagon and looks up, which is also towards the front of the cart with the driver she says, "right Lelouch". Now it is possible that she is talking to the wind/spirits, but since she spent the entire series looking for someone to truly love her and she put all this time into making that person Lelouch why would she be so happy if she was back at square one. Although she helped from time to time she never showed true interest in his plans of world peace, she was also interested in keeping him alive and progressing his powers to the point where he could take her code, so her happiness now has one meaning to me. I know that is fairly long but I wanted to make my logic clear.